I guess we all have to start somewhere! Hitboxes are odd, controls are kind of flighty. Music is very, very repetitive. You also shouldn't say things like "ladders are tricky" to write off not coding them as well as you could have. Still, it's your first thing, so it's understandable that things aren't going to work as well as they would if you had more experience. I can't give you any technical advice, since I've no real experience with ActionScript, but the big advice I can give you is keep trying and be sure to try new things. Think outside of the box. I refuse to give this lower than 2 stars since it's your first thing and you obviously did put quite a bit of effort into it, but I really can't give it more than that, either.

Dude, pushing A didn't take me left and pushing D didn't "always" take me right... It seems like the W button was the only one that never failed. Weird. couldn't get into this. I tried. Looks like it could have been fun if the controls worked.

Average platfomer, but I enjoyed it :)
Although there are a few flaws, like in the beginning where you're supposed to go left instead of the traditional right. this isn't bad, but you also leave the impression that right is the 'right' way to go. this game also has bugs, like the ladders only work(100%) when you are on the right side, and you can just hold up to go flying upwards. The song is great, but it gets seriously repetitive, ruining a wonderful piece(same goes fo the animation).
until this is all fixed i can not give it a justified score.

Considering what I was expecting, you did fantastic with this game.
It has a lot of potential, even if the graphics are quite crude. I actually had fun playing this!